When it is released from the wing, it should be decelerating until rocket engine ignites... that pushes the propellants forward to the 'top' of the tanks. What is done to 'settle' the liquids before engine ignition?

Angle the vehicle slightly upwards. That should counter the drag going forwards and settle the propellants to the bottom of the tanks.

I got the impression, from various design studies that flight angle at separation can make a huge difference in several areas regarding loads, payload to orbit etc. Like MR control during the flight, one of those subtle-but-powerful details that can have a big impact on the feasibility of a design.

Thank you @Virgin_Orbit for the tour of your facility and the opportunity to meet your work force. The technologies and capabilities in this enterprise are rapidly progressing and I appreciate your passion and dedication! #spacestartshere too!

Recently, we conducted two Launch Campaign Rehearsals—full-on sessions where our technicians and engineers prepare a LauncherOne rocket as though it were launch day and the countdown clock was ticking towards t-minus-zero.

Propellant tanks are loaded and pressurized, software is loaded up, and our mission control crew are at their consoles, overseeing it all. These rehearsals provide a great chance to test out everything from the ground support equipment to the call-outs and procedures.

It is imperative that we be safe, precise, and systematic. Since we are building a system that is designed for flexibility, it bodes well that our very first launch campaign rehearsal was completed in one extended shift—and even better that our second rehearsal was 40% faster.